Technologies such as microphones and inkjet printers are made using piezoelectric materials, which generate an internal electric field when pressure...

Sentence Structure

• Technologies such as microphones and inkjet printers
  • are made using piezoelectric materials,
    • which generate an internal electric field
      • when pressure is applied to them.

• The toxic nature of some of these materials
  • recently led a team from the University of Sheffield
    • to investigate how [could their use be better regulated / their use could be better regulated] [? / .]

Understanding the Meaning

Let's start with the first sentence to get the context:

• 'Technologies such as microphones and inkjet printers are made using piezoelectric materials'
  • These are special materials used to make common technologies

• 'which generate an internal electric field when pressure is applied to them'
  • This tells us what makes these materials special - they create electricity when you press on them

Now the second sentence:

• 'The toxic nature of some of these materials'
  • Some of these piezoelectric materials are toxic

• 'recently led a team from the University of Sheffield'
  • This toxicity caused a team of researchers to do something

• 'to investigate how ____'
  • This is where we have the blank - they were led to investigate something

Let's look at our choices:

• Some use the word order "could their use"
• Others use "their use could"
• Some end with a question mark, others with a period

To see what works here, let's understand what this structure is telling us!

The key phrase is 'to investigate how...'

• This is telling us what the team was led to study
• The word 'how' here is introducing what they investigated - it's not asking US a direct question
• We're being told about their investigation

Now, what do we notice about the structure here?

• This is an indirect question - it's reporting what was investigated, not asking the reader directly

• Compare these two structures:
  • Direct question (asking the reader): "How could their use be better regulated?"
  • Indirect question (reporting what was studied): "They investigated how their use could be better regulated."

• When we embed a question inside a statement like this, we use:
  • Regular statement word order (subject before verb): "their use could"
  • A period at the end (because the whole sentence is a statement, not a question)

So we need: "their use could be better regulated."

The complete meaning is: Because some of these materials are toxic, a research team was prompted to study how the use of these materials could be better regulated.

GRAMMAR CONCEPT APPLIED

Direct vs. Indirect Questions

When you embed a question within a statement (called an indirect question in grammar terms), the structure changes from how you'd write a direct question:

Direct Question (asking the reader directly):

• Inverted word order: auxiliary verb + subject + main verb
• Ends with question mark
• Example: "How could their use be better regulated?"

Indirect Question (embedded in a statement):

• Statement word order: subject + auxiliary verb + main verb
• Ends with period (or whatever punctuation the main sentence needs)
• Example: "They investigated how their use could be better regulated."

Common introductory phrases for indirect questions:

• "to investigate how..."
• "to study whether..."
• "wondered why..."
• "asked when..."
• "examined how..."

In our question:

• The phrase "led a team to investigate how..." introduces an indirect question
• Therefore we need: statement word order ("their use could") + period
• Answer: B